Notes

Size: I consider this massively oversized. In my experience, 50uL of PCR products (~3ug product) is more than sufficient for cloning. -Josh

I think this depends on what you're cloning. My inserts tend to be <150 bp, which means getting 3 ug of product requires significantly larger PCR volumes. Smaller inserts are also more difficult to purify without loss downstream, hence the large volume that I generally use. --YC

Polymerase: I use Pfu (>500bp) or PfuUltraII (>~3kb) for any lengthy PCR that I intend to clone. -Josh

Magnesium: I have never felt a need to vary my magnesium concentration on a reaction-by-reaction basis. So I mix my Taq buffer using a standard amount of magnesium (2mM, personally), and save an extra step. The magnesium concentration given above (0.16mM) seems way too low. -Josh